Ultrasonic surgical blade with improved heel portion

ABSTRACT

An ultrasonic surgical blade with an improved heel portion is disclosed. The blade includes a solid body, a longitudinal portion having a proximal end configured to couple to an ultrasonic transmission waveguide and a transverse portion extending crosswise from the distal end of the longitudinal portion. At least one dissection edge and at least one hemostasis surface is provided on the blade. The transverse portion defines a hook having a free end configured to pull and dissect tissue. The blade further comprises a tissue plow comprising a plow edge and a distal-most vertex to increase the efficiency of heel dissection and tissue diversion.

INTRODUCTION

The present disclosure is related generally to ultrasonic blades for use in surgical instruments. In particular, the present disclosure is related to ultrasonic surgical blades for use in surgical instruments and, more particularly, to an ultrasonic surgical blade with improved cutting and coagulation features.

BACKGROUND

Ultrasonic instruments, including both hollow core and solid core instruments, are used for the safe and effective treatment of many medical conditions. Ultrasonic instruments, and particularly solid core ultrasonic instruments, are advantageous because they may be used to cut and/or coagulate organic tissue using energy in the form of mechanical vibrations transmitted to a surgical end-effector at ultrasonic frequencies. Ultrasonic vibrations, when transmitted to organic tissue at suitable energy levels and using a suitable end-effector, may be used to cut, dissect, or cauterize tissue. Ultrasonic instruments utilizing solid core technology are particularly advantageous because of the amount of ultrasonic energy that may be transmitted from the ultrasonic transducer, through the waveguide, to the surgical end-effector. Such instruments may be used for open procedures or minimally invasive procedures, such as endoscopic or laparoscopic procedures, wherein the end-effector is passed through a trocar to reach the surgical site.

Activating the end-effector (e.g., cutting blade) of such instruments at ultrasonic frequencies induces longitudinal vibratory movement that generates localized heat within adjacent tissue, facilitating both cutting and coagulation. Because of the nature of ultrasonic instruments, a particular ultrasonically actuated end-effector may be designed to perform numerous functions, including, for example, cutting and coagulation. The structural stress induced in such end-effectors by vibrating the blade at ultrasonic frequencies may have a number of undesirable effects. Such undesirable effects may include, for example, transverse motion in the instrument waveguide that may lead to, for example, excess heat generation in the waveguide or premature stress failure.

Although ultrasonic surgical instruments have been eminently successful, some areas of improvement still remain. For example, it would be desirable for improved ultrasonic blades to remove the gall bladder from the liver bed and for coagulation to facilitate the procedure. An ultrasonic blade that enables efficient dissection of the gall bladder from the liver bed using proximal and distal surfaces facilitates the surgical technique. An ultrasonic blade which has a hook or right angle, or near right angle, bend near the distal end with a plow member, or ridge cutting edge, at the distal end would provide advantages for access and visibility. The challenges to providing such a configuration have been stress and balance related. An ultrasonic blade with such a configuration must be behave in a balanced manner and be sufficiently strong to endure the added stresses. It would, therefore, be desirable to design an improved ultrasonic surgical blade. It would further be advantageous to provide an ultrasonic surgical blade that cuts faster, while maintaining hemostasis desired by the surgeon. It would also be advantageous to provide an ultrasonic surgical blade that is more controllable and precise, to providing cutting where needed with significant control.

Additionally, surgeons may utilize the leading, or distal, portion of the ultrasonic surgical blade, also referred to as the heel of the blade, when dissecting the gall bladder from the liver bed for cutting tissue as well as efficiently advancing the blade between the gall bladder and the liver bed. Thus, it would be advantageous to provide an ultrasonic surgical blade with an improved heel portion to optimize heel dissection. It would also be advantageous to provide an improved heel configuration to allow a surgeon to more easily enter the tissue plane between the gall bladder and the liver bed.

An ultrasonic surgical instrument is described with improved cutting and coagulation features to provide these advantages and overcome the disadvantages of previous instruments.

SUMMARY

In one aspect, an ultrasonic surgical blade is disclosed. In one example, an ultrasonic surgical blade comprises a solid body; a longitudinal portion having a proximal end configured to couple to an ultrasonic transmission waveguide and a distal end configured to dissect and coagulate tissue, the longitudinal portion comprising: a substantially planar longitudinal surface; and a distal hemostasis surface located opposite of the substantially planar longitudinal surface; a transverse portion extending crosswise from the distal end of the longitudinal portion, the transverse portion defining a hook having a free end configured to pull and dissect tissue, the transverse portion comprising: a curved section extending from a distal end of the substantially planar longitudinal surface; a tip surface defined at the free end; a substantially planar proximal inner surface extending from the curved surface to the tip surface; and a plow member extending from the tip surface to the distal hemostasis surface, the plow member comprising first and second lateral surfaces extending from a surface inflection defining a cutting edge; and a distal dissection edge defined at a surface inflection of the first and second distal lateral surfaces and the distal hemostasis surface.

In another example, the distal dissection edge of the ultrasonic surgical blade comprises a distal-most vertex defined by the plow member and the distal hemostasis surface.

In another example, the plow member of the ultrasonic surgical blade is concave.

In another example the ultrasonic surgical blade further comprises a leading, angular tip surface extending from the tip surface to the first and second lateral surfaces.

In another example, the first and second lateral surfaces of the ultrasonic surgical blade each comprises a surface section, and wherein each surface section is concave.

In another example, the longitudinal portion of ultrasonic surgical blade comprises a proximal hemostasis surface located opposite of the substantially planar longitudinal surface. In another example, the ultrasonic surgical blade further comprising first and second proximal lateral surfaces extending from the body to the proximal hemostasis surface defining first and second lateral cutting edges defined at first and second surface inflections between the first and second proximal lateral surfaces and the proximal hemostasis surface.

In another example, the ultrasonic surgical blade further comprises a beveled edge defined between the tip surface and the substantially planar proximal inner surface.

In another aspect, an ultrasonic surgical blade is disclosed. In one example, the ultrasonic surgical blade comprises a solid body; a longitudinal portion having a proximal end and a distal end, the longitudinal portion comprising: a substantially planar longitudinal surface; and a distal hemostasis surface located opposite of the substantially planar longitudinal surface; a transverse portion extending crosswise from the distal end of the longitudinal portion, the transverse portion defining a hook having a free end, the transverse portion comprising: a curved section extending from a distal end of the substantially planar longitudinal surface; a tip surface defined at the free end; a proximal inner surface extending from the curved surface to the tip surface; and a tissue diverting portion extending from the tip surface to the distal hemostasis surface, the tissue diverting portion comprising a tissue diverting edge.

In another example, the tissue diverting edge of the ultrasonic surgical blade is concave.

In another example, the ultrasonic surgical blade further comprising a distal-most vertex defined by the tissue diverting portion and the distal hemostasis surface.

In another example, the ultrasonic surgical blade further comprises a distal dissection edge defined by a surface inflection of the distal hemostasis surface and the tissue diverting portion, and wherein the distal dissection edge and the tissue diverting edge comprises a substantially T-like configuration.

In another example, the longitudinal portion of the ultrasonic surgical blade comprises a proximal hemostasis surface located opposite of the substantially planar longitudinal surface. In another example, the ultrasonic surgical blade comprises first and second lateral surfaces extending from the body to the proximal hemostasis surface defining first and second cutting edges defined at first and second surface inflections between the first and second lateral surfaces and the proximal hemostasis surface.

In another aspect, an ultrasonic surgical blade is disclosed. In one example, the ultrasonic surgical blade comprises a hook portion having a free end portion and a distal end; and a plow member defined by the distal end of the hook portion, the plow member comprising first and second lateral surfaces extending from a surface inflection defining a cutting edge.

In another example, the plow member of the ultrasonic surgical blade is configured to divert tissue upon interaction therewith.

In another example, the plow cutting edge of the ultrasonic surgical blade is concave.

In another example, the cutting edge of the ultrasonic surgical blade extends from a vertex defined at a first end of the cutting edge to a tip surface defined at a second end of the cutting edge.

In another example, the ultrasonic surgical blade further comprises an angular tip surface defined by the free end portion of the hook portion.

In another example, the first and second lateral surfaces of the ultrasonic surgical blade are curved.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, and features described above, further aspects, and features will become apparent by reference to the drawings and the following detailed description.

FIGURES

The novel features of the aspects described herein are set forth with particularity in the appended claims. The aspects, however, both as to organization and methods of operation may be better understood by reference to the following description, taken in conjunction with the accompanying drawings as follows.

FIG. 1 is an illustration of an ultrasonic instrument according to one aspect.

FIG. 2 is an illustration of the ultrasonic instrument shown in FIG. 1, with the outer sheath removed to reveal the underlying ultrasonic transmission waveguide.

FIG. 3 is an illustration of the ultrasonic surgical instrument shown in FIG. 1 with the right and left shrouds removed.

FIG. 4 is an illustration of the handle assembly of the ultrasonic surgical instrument shown in FIG. 1 with the left shroud, the shaft assembly, and the nose cone removed.

FIG. 5 is a front view of the ultrasonic surgical instrument shown in FIG. 1 with the nose cone removed to show the underlying activation button assembly, the clutch plate, retainer, and support bushing.

FIG. 6 is a graphical representation of displacement (microns) along the vertical axis of the ultrasonic surgical blade shown in FIGS. 1-5 versus distance (in) along the ultrasonic surgical blade along the horizontal axis, according to one aspect.

FIG. 7 illustrates another aspect of a surgical end effector integrally formed with an ultrasonic transmission waveguide.

FIG. 8 is a perspective view of an ultrasonic surgical blade of the surgical end effector of FIG. 7.

FIG. 9 is a side view of the ultrasonic surgical blade of FIG. 8.

FIG. 10 is a perspective view of the ultrasonic surgical blade of FIG. 8.

FIG. 11 is a bottom view of the ultrasonic surgical blade of FIG. 8, wherein the ultrasonic surgical blade comprises a distal and proximal hemostasis surface.

FIG. 12 is another side view of the ultrasonic surgical blade of FIG. 8.

FIG. 13 is cross-sectional view of the ultrasonic surgical blade of FIG. 8 taken along line 13-13 shown in FIG. 12.

FIG. 14 is another cross-sectional view of the ultrasonic surgical blade of FIG. 8 taken along line 14-14 shown in FIG. 12.

FIG. 15 is a top view of the ultrasonic surgical blade of FIG. 8.

FIG. 16 is a cross-sectional view of the ultrasonic surgical blade of FIG. 8 taken along line 16-16 shown in FIG. 15.

FIG. 17 is a front view of the ultrasonic surgical blade of FIG. 8.

DESCRIPTION

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols and reference characters typically identify similar components throughout the several views, unless context dictates otherwise. The illustrative aspects described in the detailed description, drawings, and claims are not meant to be limiting. Other aspects may be utilized, and other changes may be made, without departing from the scope of the subject matter presented here.

The following description of certain examples of the technology should not be used to limit its scope. Other examples, features, aspects, aspects, and advantages of the technology will become apparent to those skilled in the art from the following description, which is by way of illustration, one of the best modes contemplated for carrying out the technology. As will be realized, the technology described herein is capable of other different and obvious aspects, all without departing from the technology. Accordingly, the drawings and descriptions should be regarded as illustrative in nature and not restrictive.

It is further understood that any one or more of the teachings, expressions, aspects, examples, etc. described herein may be combined with any one or more of the other teachings, expressions, aspects, examples, etc. that are described herein. The following-described teachings, expressions, aspects, examples, etc. should therefore not be viewed in isolation relative to each other. Various suitable ways in which the teachings herein may be combined will be readily apparent to those of ordinary skill in the art in view of the teachings herein. Such modifications and variations are intended to be included within the scope of the claims.

In the following description, it is to be understood that terms such as front, back, inside, outside, top, bottom and the like are words of convenience and are not to be construed as limiting terms. Terminology used herein is not meant to be limiting insofar as devices described herein, or portions thereof, may be attached or utilized in other orientations. The various aspects will be described in more detail with reference to the drawings. Several examples of ultrasonic blades and instruments are disclosed in U.S. patent application Ser. No. 14/789,744, entitled ULTRASONIC SURGICAL BLADE WITH IMPROVED CUTTING AND COAGULATION FEATURES, filed Jul. 1, 2015 which is hereby incorporated by reference herein in its entirety.

The present disclosure provides an ultrasonic instrument comprising an ultrasonic blade with improved cutting and coagulation features. FIG. 1 is an illustration of an ultrasonic instrument 100 according to one aspect. The ultrasonic instrument 100 comprises a handle assembly 102, a shaft assembly 104, and a surgical end-effector 106. The handle assembly 102 comprises right and left shrouds 108 a, 108 b, an activation button assembly 110, and a nose cone 112. The activation button assembly 110 comprises a plurality of activation buttons. Turning briefly to FIG. 5, which is a front view of the ultrasonic instrument, it can be seen that in one aspect, the activation button assembly 110 comprises eight activation buttons 110 a, 110 b, 110 c, 110 d, 110 e, 110 f, 110 g, 110 h distributed about the handle assembly 102. Turning back to FIG. 1, the shaft assembly 104 comprises an outer sheath 114. The surgical end-effector 106 comprises an ultrasonic surgical blade 116 with improved cutting and coagulation features. For example, the ultrasonic blade 116 comprises a plow member, or ridge cutting edge, 591 to separate tissue. The ultrasonic surgical blade 116 and ultrasonic transmission waveguide is isolated from the outer sheath 114 with multiple isolation spacers 118, which can be overmolded over the ultrasonic transmission waveguide.

The handle assembly 102 also comprises an ultrasonic transducer acoustically coupled to an ultrasonic transmission waveguide which is acoustically coupled to the surgical end-effector 106. The handle assembly 102 is electrically connected to an ultrasonic energy generator, which can be activated by one of the plurality of activation buttons 110 a-110 h, for example the activation button 110 a. Depressing the activation button 110 a activates the ultrasonic generator, and delivers electrical energy to an ultrasonic transducer located in the handle assembly 102. The ultrasonic transducer in the handle assembly 102 converts the electrical energy to ultrasonic motion, which is acoustically coupled to the ultrasonic transmission assembly and the treatment region of the surgical end-effector 106. The treatment region vibrates at an excursion magnitude of 20 micrometers to 150 micrometers, and at a frequency of approximately 55.5 kilohertz, although other frequencies may be employed, without departing from the scope of the present disclosure.

FIG. 2 is an illustration of the ultrasonic instrument 100 shown in FIG. 1, with the outer sheath 114 (FIG. 1) removed to reveal the underlying ultrasonic transmission waveguide 120. As shown, isolation spacers 118 are disposed over the ultrasonic transmission waveguide 120 to acoustically isolate the outer sheath 114 from the ultrasonic transmission waveguide 120. Accordingly, the plurality of isolation spacers 118 are located on respective nodes along the ultrasonic transmission waveguide 120 to minimize the vibrations acoustically coupled to the outer sheath 114. In one aspect, the isolation spacers 118 may be overmolded over the ultrasonic transmission waveguide 120.

FIG. 3 is an illustration of the ultrasonic surgical instrument 100 shown in FIG. 1 with the right and left shrouds 108 a, 108 b removed. The handle assembly 102 includes a support base 122 located proximal to the activation button assembly 110.

FIG. 4 is an illustration of the handle assembly 102 of the ultrasonic surgical instrument 100 shown in FIG. 1 with the left shroud 108 b (FIG. 1), the shaft assembly 102 (FIG. 1), and the nose cone 112 removed. As shown in FIG. 4, below the nose cone 112 is a bridge guide 132 operatively coupled to the activation button assembly 110. A clutch plate 134 and clutch spring 136 are disposed between the bridge guide 132 and a retainer 138. A support bushing 140 supports the shaft assembly 102.

FIG. 5 is a front view of the ultrasonic surgical instrument 100 shown in FIG. 1 with the nose cone 112 removed to show the underlying activation button assembly 110, the clutch plate 134, retainer 138, and support bushing 140. The activation button assembly 110 comprises a plurality activation buttons 110 a-110 h, that are individually programmable to perform a particular function. For example, the activation 110 a is electrically coupled to the ultrasonic generator and is used to energize the ultrasonic transducer to activate the surgical end-effector 106.

FIG. 6 is a graphical representation 162 of displacement (microns) along the vertical axis of the ultrasonic surgical blade 116 shown in FIGS. 1-5 versus distance (in) along the ultrasonic surgical blade 116 along the horizontal axis, according to one aspect. The distance along the blade indicated as 0.000 in. corresponds to the most proximal location where the ultrasonic transmission waveguide 120 and the distance along the blade indicated as 14.000 in. corresponds to the most distal location 166 where the ultrasonic tip 144 of the ultrasonic surgical blade 116 is displaced. With reference now also to FIG. 6, the blade displacement waveform 164 represented by the solid line is a standing waveform set up in the ultrasonic transmission waveguide and end effector ultrasonic surgical blade 116 along the longitudinal axil L as shown in FIG. 6. The displacement waveform 164 includes periodic nodes 174 and antinodes 176, 176′ at locations along the longitudinal axis L. The nodes 174 are locations along the standing waveform 164 where there is no displacement and antinodes 176 are locations where displacement is maximum positive, and antinodes 176′ where displacement is maximum negative. In accordance with the periodic nature of the ultrasonic vibrations and the properties of a standing wave 164, the nodes 174 and antinodes 176, 176′ are located at a distance equal to one quarter wavelength λ/4, where the wavelength λ proportional to the frequency of vibrations f_(o) and the speed c of sound in the material of the transmission waveguide and the ultrasonic surgical blade 116 according to the following relationship f_(o)=2πλ/c. Due to the design of the ultrasonic surgical blade 116, it can be seen that the absolute maximum displacement occurs at the distal antinode 178, which corresponds to the location of the antinode AN in FIG. 6.

FIGS. 7-17 illustrate one aspect of an ultrasonic surgical blade 516 configured with edges and surfaces to optimize hemostasis and dissection. Specifically, a heel portion 517 of the blade 516 provides a user with a configuration that permits the blade 516 to be navigated within the tissue plane more efficiently when dissecting the gall bladder from the liver bed, for example. A distal cutting edge 591 defines a configuration resembling a plow member, or ridge, to facilitate tissue diversion when navigating the blade 516 between tissue mediums. Edges and features such as a distal-most vertex, disposed on the distal portion of the ultrasonic surgical blade 516 can provide more efficient heel dissection.

FIG. 7 is a perspective view of one aspect of an ultrasonic surgical instrument 500 comprising an end effector 506 integrally formed with an ultrasonic transmission waveguide 520. The ultrasonic surgical instrument 500 is similar in many respects to the ultrasonic surgical instrument 100. The surgical end effector 506 comprises an ultrasonic surgical blade 516 having a neck 542 coupled to the ultrasonic transmission waveguide 520. The ultrasonic transmission waveguide 520 is a component of a shaft assembly 504 and may be acoustically isolated from other components of the shaft assembly 504, such as the outer sheath 514 (FIG. 12), by an isolation spacer. As previously discussed in connection with FIG. 15, the isolation spacers are located at the nodes of the ultrasonic transmission waveguide where vibrations are at a minimum or zero amplitude. The ultrasonic surgical blade 516 is configured to vibrate in response to ultrasonic energy applied thereto via the ultrasonic transmission waveguide 520. A balance feature 543 is defined as a cutout section in the ultrasonic transmission waveguide 520 to facilitate the expansion and contraction of the ultrasonic transmission waveguide 520 during the vibratory process.

FIG. 8 is a perspective view of one aspect of the ultrasonic surgical blade 516. The distal portion of the ultrasonic surgical blade 516 has a curved or angular shape that defines a blade hook 550 having a free end configured for pulling and cutting tissue during use. The ultrasonic surgical blade 516 comprises a longitudinal portion 541 extending distally from the neck 542, where it couples to ultrasonic vibrations and a transverse portion 547 extending from a distal end of the longitudinal portion 541. The transverse portion 547 of the ultrasonic surgical blade 516 defines the blade hook 550 and a tissue-plow configuration 590. At the end of the transverse portion 547, the blade hook 550 defines a tip surface 544 optimized to access tissue planes. From the tip surface 544, extending outwardly and toward the distal cutting edge configuration 590, the tip surface 544 transitions at a surface inflection 539 to a leading, angular tip surface 545. In various instances the tip surface 545 comprises a convex profile. In various other instances, the tip surface 545 comprises a substantially flat or concave profile. The tip surface 545 can be oblique and/or triangular-like. The tip surface 545 comprises a distal vertex 545V defining the distal cutting edge 591 which resembles a plow member or ridge. The plow edge, or sharp vertical ridge, of the distal cutting edge 591 comprises a concave radius of curvature. In various instances, the distal cutting edge 591 can comprise portions that are not curved as well as portions that are curved. Extending from the tip surface 545 at a pair of surface inflections, or edges, 553A and 553B, the blade hook 550 defines a pair lateral distal surfaces 552 which share a common edge 591 defining the distal cutting edge. The distal cutting edge 591 is also referred to as a plow edge, or a ridge feature. The tissue plow configuration 590 is configured to facilitate access to tissue planes by diverting the tissue with the plow edge 591. In various instances, the surfaces 552 define concave radii of curvatures. In various other instances, the surfaces 552 are substantially flat and are comprised of multiple substantially flat portions meeting a surface inflection. In various instances, the surfaces 552 comprise curved and flat surfaces.

Extending from the distal lateral surfaces 552 through yet another surface inflection is a distal hemostasis surface 548 defining a larger surface area. The distal hemostasis surface 548 has a convex radius of curvature. A dissection edge 546 is defined at the surface inflection between the lateral surfaces 552 and the distal hemostasis surface 548. The dissection edge 546 is configured to improve the dissection or cutting speed using the heel portion 517 of the ultrasonic surgical blade 516. The plow configuration 590 comprises a distal-most vertex 592 disposed along the dissection edge 546 and is configured to lead the ultrasonic surgical blade into the tissue planes. The concave profile of the plow edge 591 extends distally at the surface inflection defining the dissection edge 546 such that the transverse portion 547 of the hook 550 is tapered from the dissection edge 546 to the tip surface 545. From the surface inflections 553A, 553B, the tip surface 545 extends at an angle to the tip surface 544.

The inner, proximal, portion of the blade hook 550 defines a substantially planar inner surface 549 on the proximal side of the blade hook 550 that extends along the transverse portion 547 from a beveled edge 582 of the tip surface 544 to a curved surface 551 having a concave radius of curvature r₁. The depth d₁ of the transverse portion 547 measured from the tip surface 544 to the planar longitudinal surface 561 may be optimized to pull tissue of various types. A proximal hemostasis surface 554 is provided on the longitudinal portion 541 of the ultrasonic surgical blade 516 and is sized to deliver suitable hemostasis while minimizing mass.

FIG. 9 is a side view of the ultrasonic surgical blade 516 shown in FIGS. 7 and 8. The ultrasonic surgical blade 516 further comprises additional surfaces designed to acoustically balance the ultrasonic surgical blade 516. These surfaces include a first lateral surface 556, a second lateral surface 558, and a third lateral surface 560 located on one side of the ultrasonic surgical blade 516 and corresponding lateral surfaces on the other side of the ultrasonic surgical blade 516, which are labeled by a prime (′) (FIG. 12). The lateral surfaces 560, 560′ are oblique and extend from a proximal body portion 559 of the blade 516 to the proximal hemostasis surface 554. Cutting edges 565, 565′ are defined at the surface inflections of the proximal hemostasis surface 554 and the oblique lateral surfaces 560, 560′. The lateral surfaces 556, 556′, 558, 558′, 560, 560′ are produced by removing mass from the blade body 559 and are contoured to balance the ultrasonic surgical blade 516 to provide stable ultrasonic vibrations when energized. The substantially planar longitudinal surface 561 is part of the longitudinal portion 541 of the ultrasonic surgical blade 516 extending from the neck 542 toward the curved surface 551 of the transverse portion 547 of the blade hook 550.

FIG. 10 is another perspective view of the ultrasonic surgical blade 516 shown in FIGS. 7-9. The view illustrated in FIG. 10 shows the surface areas of each surface 548, 554. The sizes of the distal and proximal hemostasis surfaces 548, 554 are dimensioned to deliver suitable hemostasis while minimizing mass. The surface inflection 565′ of the proximal hemostasis surface 554 and the lateral surface 560′ define a cutting edge. The proximal hemostasis surface also defines a cutting edge 570′. Discussed in greater detail below, a cutting edge 572′ is disposed on the heel portion 517 of the blade 516.

FIG. 11 is a partial, bottom view of the ultrasonic surgical blade 516 shown in FIGS. 7-10. The distal hemostasis surface 548 defines a distal dissection edge 546 and lateral sharp cutting edges 572, 572′. The cutting edges 572, 572′ share the vertex 592. The cutting edge 572 comprises a first concave portion and a second concave portion sharing an intermediate vertex. Similarly, the cutting edge 572′ comprises a first concave portion and a second concave portion sharing an intermediate vertex. The distal hemostasis surface 548 has an effective surface area S1 of approximately 3.25 mm² and may vary over a range of 3.25 mm² to 6.0 mm² (0.0053 in² to 0.0093 in²). The proximal hemostasis surface 554 defines lateral sharp cutting edges 570, 570′. The proximal hemostasis surface 554 has an effective surface area S2 of approximately 9.675 mm² and may vary over a range of 6.45 mm² to 12.90 mm² (0.01 in² to 0.02 in²).

FIG. 12 is another side view of the ultrasonic surgical blade 516 shown in FIGS. 7-11. Similar to FIG. 9, the view shown in FIG. 12 illustrates the corresponding lateral surfaces labeled by a prime (′). These surfaces include a first lateral surface 556′, a second lateral surface 558′, and a third lateral surface 560′ located on the other side of the ultrasonic surgical blade 516. The lateral surfaces 560, 560′ are oblique and extend from a proximal body portion 559 of the blade 516 to the proximal hemostasis surface 554. Cutting edges 565, 565′ are defined at the surface inflections of the proximal hemostasis surface 554 and the oblique lateral surfaces 560, 560′. The lateral surfaces 556, 556′, 558, 558′, 560, 560′ are produced by removing mass from the blade body 559 and are contoured to balance the ultrasonic surgical blade 516 to provide stable ultrasonic vibrations when energized. The substantially planar longitudinal surface 561 is part of the longitudinal portion 541 of the ultrasonic surgical blade 516 extending from the neck 542 toward the curved surface 551 of the transverse portion 547 of the blade hook 550. The neck 542 extends distally from the sheath 514 and transitions into the body portion 559.

FIG. 13 is a cross-sectional view of the ultrasonic surgical blade 516 shown in FIGS. 7-12 taken along section line 12-12 in FIG. 12. Also shown is the longitudinal extending portion 541 of the blade hook 550.

FIG. 14 is a cross-sectional view of the ultrasonic surgical blade 516 shown in FIGS. 7-13 taken along section line 14-14 in FIG. 12. The surfaces 552 comprise curved, or plow surface, sections 552′. The curved profile of the sections 552′ provide the ridge 591 with its concave radius of curvature. As discussed above, the surfaces 552 can comprise flat and curved sections, thus, the ridge, or edge, 591 can comprise flat and/or curved sections.

FIGS. 15-17 provide additional views of the ultrasonic surgical blade 516 shown in FIGS. 7-14. FIG. 15 is a top view of the ultrasonic surgical blade 516. From left to right, the neck 542 extends distally from the outer tube/sheath 514 and transitions into the blade body portion 559 at surface inflection 586. The blade body 559 defines several surfaces for cutting and/or pulling tissue, applying hemostasis to the tissue, and/or acoustically balancing the ultrasonic surgical blade 516. Additionally, the blade body 559 comprises a heel portion 517 configured to allow a surgeon to dissect tissue with a distal portion of the blade 516 as well as more easily navigate the blade 516 into tissue planes. The planar longitudinal surface 561 extends from a proximal end of the blade body 559 to the curved surface 551 of the blade hook 550. The inner surface 549 of the blade hook 550 extends from the curved surface 551 to the beveled surface 582 of the tip surface 544. The tip surface 544 transitions to the tip surface 545 at surface inflection 539. In various instances, the tip surface 545 comprises a substantially triangular configuration defining the edges 553A, 553B wherein the distal lateral surfaces 552 extend from the edges 553A, 553B to the dissection edge 546, defining a distal, prism-like structure disposed on a distal portion of the blade 516. The most distal portion of the distal surfaces 552 defines the dissection edge 546 which is also the surface inflection between the distal surface 552 and the distal hemostasis surface 548 (FIG. 17). The most distal portion of the dissection edge 546 is the vertex 592 where the sharp distal ridge 591 and the dissection edge 546 meet, or intersect.

FIG. 16 is a cross-sectional view of the ultrasonic surgical blade 516 taken along section line 16-16 shown in FIG. 15. This sectional view is taken along a longitudinal centerline to show various features of the ultrasonic surgical blade 516 previously described. From right to left, as the blade body 559 extends from the blade neck 542, the ultrasonic surgical blade 516 defines a first surface inflection 568 between the blade body 559 and the planar longitudinal surface 561. The hook portion 550 is defined in part by the curved surface 551 and the inner surface 549 up to the beveled surface 582. The tip surface 544 transitions to the tip surface 545 at surface inflection 539. The tip surface 545 transitions to the distal surfaces 552 at surface inflections 553A, 553B. The distal surfaces 552 share the distal ridge 591 and transition to the distal hemostasis surface 548 at the surface inflection 546, which also defines the dissection edge 546. In various instances, the distal cutting edge 591 is concave. The distal cutting edge 591 defined by the plow member extends from the tip surface 545 to a distal-most vertex 592 of the dissection edge 546. For purposes of the present disclosure, the surface inflection 546 and the dissection edge 546 refer to the same elements. The distal hemostasis surface 548 transitions to the proximal hemostasis surface 554 at surface inflection 555. The proximal hemostasis surface 554 transitions to the blade body 559 at surface inflection 565.

FIG. 17 is an end view of the ultrasonic surgical blade 516. As shown, the transverse portion 547 of the ultrasonic surgical blade 516 comprises a tip surface 544 that transitions into the tip surface 545 at surface inflection 539. The distal surfaces 552 extend from the tip surface 545 at surface inflections 553A, 553B. In various instances, the distal surfaces 552 are oriented at a 45 degree angle with respect to a longitudinal axis defined by the shaft assembly 504, for example. In other instances, the distal surfaces 552 are oriented at angles other than 45 degrees. The configuration of the surfaces 552 permit this plow-like configuration to divert tissue upon entry into a tissue plane, for example. The surfaces 552 and/or 552′ can be referred to as tissue diverting portions. Steeper profiles for the tissue plow configuration 590 are contemplated. For example, the angle between the inflections 553A, 553B can be acute which would provide a sharper profile for the plow 590. In various other instances, the angle between the inflections 553A, 553B can be obtuse which would provide a less sharp, or less steep, profile for the plow 590. The distal surfaces 552 define the dissection edge 546 between the distal hemostasis surface 554 and the distal surfaces 552.

Referring still to FIG. 17, the ridge 591 and the dissection edge 546 comprise a substantially T-like configuration, or profile. This T-like configuration, along with the distal-most vertex 592 can provide the ultrasonic surgical blade 516 with horizontal heel dissection and vertical heel dissection. This configuration also maintains a distal hemostasis surface increasing the versatility of the heel portion 517 of the ultrasonic surgical blade 516. Tissue can be quickly and more efficiently incised and/or diverted with the plow configuration 590.

As discussed herein, any reference to “one aspect” or “an aspect” means that a particular feature, structure, or characteristic described in connection with the aspect is included in at least one aspect. Thus, appearances of the phrases “in one aspect” or “in an aspect” in various places throughout the specification are not necessarily all referring to the same aspect. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more aspects.

Although various aspects have been described herein, many modifications, variations, substitutions, changes, and equivalents to those aspects may be implemented and will occur to those skilled in the art. Also, where materials are disclosed for certain components, other materials may be used. It is therefore to be understood that the foregoing description and the appended claims are intended to cover all such modifications and variations as falling within the scope of the disclosed aspects. The following claims are intended to cover all such modification and variations.

Although various aspects have been described herein, many modifications, variations, substitutions, changes, and equivalents to those aspects may be implemented and will occur to those skilled in the art. Also, where materials are disclosed for certain components, other materials may be used. It is therefore to be understood that the foregoing description and the appended claims are intended to cover all such modifications and variations as falling within the scope of the disclosed aspects. The following claims are intended to cover all such modification and variations. 

What is claimed is:
 1. An ultrasonic surgical blade, comprising: a solid body; a longitudinal portion having a proximal end configured to couple to an ultrasonic transmission waveguide and a distal end configured to dissect and coagulate tissue, the longitudinal portion comprising: a substantially planar longitudinal surface; and a distal hemostasis surface located opposite of the substantially planar longitudinal surface; a transverse portion extending crosswise from the distal end of the longitudinal portion, the transverse portion defining a hook having a free end configured to pull and dissect tissue, the transverse portion comprising: a curved section extending from a distal end of the substantially planar longitudinal surface; a tip surface defined at the free end; a substantially planar proximal inner surface extending from the curved section to the tip surface; and a plow member extending from the tip surface to the distal hemostasis surface, the plow member comprising first and second lateral surfaces extending from a surface inflection defining a cutting edge; and a distal dissection edge defined at a surface inflection of the first and second lateral surfaces and the distal hemostasis surface.
 2. The ultrasonic surgical blade of claim 1, wherein the distal dissection edge comprises a distal-most vertex defined by the plow member and the distal hemostasis surface.
 3. The ultrasonic surgical blade of claim 1, wherein the plow member is concave.
 4. The ultrasonic surgical blade of claim 1, further comprising a leading, angular tip surface extending from the tip surface to the first and second lateral surfaces.
 5. The ultrasonic surgical blade of claim 1, wherein the first and second lateral surfaces each comprises a surface section, and wherein each surface section is concave.
 6. The ultrasonic surgical blade of claim 1, wherein the longitudinal portion comprises a proximal hemostasis surface located opposite of the substantially planar longitudinal surface.
 7. The ultrasonic surgical blade of claim 6, further comprising first and second proximal lateral surfaces extending from the solid body to the proximal hemostasis surface defining first and second lateral cutting edges defined at first and second surface inflections between the first and second proximal lateral surfaces and the proximal hemostasis surface.
 8. The ultrasonic surgical blade of claim 1, further comprising a beveled edge defined between the tip surface and the substantially planar proximal inner surface.
 9. An ultrasonic surgical blade, comprising: a solid body; a longitudinal portion having a proximal end and a distal end, the longitudinal portion comprising: a substantially planar longitudinal surface; and a distal hemostasis surface located opposite of the substantially planar longitudinal surface; a transverse portion extending crosswise from the distal end of the longitudinal portion, the transverse portion defining a hook having a free end, the transverse portion comprising: a curved section extending from a distal end of the substantially planar longitudinal surface; a tip surface defined at the free end; a proximal inner surface extending from the curved section to the tip surface; and a tissue diverting portion extending from the tip surface to the distal hemostasis surface, the tissue diverting portion comprising a tissue diverting edge; and a distal dissection edge defined by a surface inflection of the distal hemostasis surface and the tissue diverting portion.
 10. The ultrasonic surgical blade of claim 9, wherein the tissue diverting edge is concave.
 11. The ultrasonic surgical blade of claim 9, further comprising a distal-most vertex defined by the tissue diverting portion and the distal hemostasis surface.
 12. The ultrasonic surgical blade of claim 9, wherein the distal dissection edge and the tissue diverting edge comprises a substantially T-like configuration.
 13. The ultrasonic surgical blade of claim 9, wherein the longitudinal portion comprises a proximal hemostasis surface located opposite of the substantially planar longitudinal surface.
 14. The ultrasonic surgical blade of claim 13, comprising first and second lateral surfaces extending from the solid body to the proximal hemostasis surface defining first and second cutting edges defined at first and second surface inflections between the first and second lateral surfaces and the proximal hemostasis surface.
 15. An ultrasonic surgical blade, comprising: a hook portion having a free end portion and a distal end; a plow member defined by the distal end of the hook portion, the plow member comprising first and second lateral surfaces extending from a first surface inflection defining a cutting edge; a distal hemostasis surface extending from a second surface inflection defined by the first and second lateral surface; and a distal dissection edge defined by a third surface inflection of the distal hemostasis surface and the plow member.
 16. The ultrasonic surgical blade of claim 15, wherein the plow member is configured to divert tissue upon interaction therewith.
 17. The ultrasonic surgical blade of claim 15, wherein the plow member cutting edge is concave.
 18. The ultrasonic surgical blade of claim 15, wherein the cutting edge extends from a vertex defined at a first end of the cutting edge to a tip surface defined at a second end of the cutting edge.
 19. The ultrasonic surgical blade of claim 15, further comprising an angular tip surface defined by the free end portion of the hook portion.
 20. The ultrasonic surgical blade of claim 19, wherein the first and second lateral surfaces are curved. 